This invention relates to device for adjusting the power output of a microwave oven, and more particularly, a device for adjusting the power output of a microwave oven which has two knobs for operating the time control unit and a power output control member, respectively.
A typical microwave oven, shown in FIG. 4, comprises a body 40, and a door 50 hingedly attached at one vertical side of the body 40 for opening/closing a front opening of a heating compartment 80. At the front surface of the body 40 a control panel portion 60 is disposed beside the door 50. On the control panel portion 60 a control device 70 is provided for adjusting the output of power.
The control device 70, shown in FIG. 5, comprises an operating time control member 71 for controlling cooking time and an output control member 72 for controlling the magnitude of magnetron (not shown) output at various step levels. Both control members 71,72 are attached to a bracket 74 in a vertically spaced manner. A first rotating shaft 75 protrudes from the operating time control member 71 and extends through an opening 61 of the control panel portion 60, while a second rotating shaft 76 protrudes from output control member 72. At respective free ends of rotating shafts 75,76 respective knobs 77,78 are mounted for convenience of manual control. Since the size of the gripping portion of respective knobs 77,78 is adapted to the fingers of a user, the distance between the rotating shafts 75,76 is inevitably relatively far. That causes the length of the bracket 74 supporting both rotating shafts 75,76 to be relatively long.
In a microwave oven having a conventional control device 70, foods are placed in the heating compartment 80 first. Depending on the characteristics of food items, the output level and the operating time are selected. The knob 78 for the second rotating shaft 76 is rotably set to point to the appropriate power level, and next, the knob 77 for the first rotating shaft 75 is set to indicate the selected time range, also.
But, since knobs 77,78 are located at the different positions, i.e. knobs directly connected to respective rotating shafts 75,76 are distanced from each other, the working line of the user's hand is required to move some distance, which causes inconvenience for the user. Further, the lengthy bracket caused by the distanced knobs reduces the compactness of the control device 70. Furthermore, the multiple knobs positions take away from the appearance of the control panel portion 60.